Can I flower yet? (space issue)

I have 4 plants that have been in veg now for 4.5 weeks (since plant broke soil) and they are currently 9-11 inches tall (3 are 9 inches, 1 is 11 inches). They are not yet alternating nodes so I guess they are not yet mature. I know that you usually wait for alternating nodes to induce flowering but I am worried about space as from what I previously read they will grow quite a bit once put into flower.

I cannot yet see preflowers either so I have no idea if they are male or female. They are in 1 gallon pots right now and will be placed into 3 gallon as their final home. I am trying to wait to do this until just before flower.

I have attached pictures that may help with the answer. I can take more if needed.

I have a total grow area (vertical) of roughly 2.5 feet. That does not include space for lights and the pot (I already subtracted that amount to come up with the 2.5 feet of grow room).

Thank you for any help that you can offer.

Looking at the pictures you can flower anytime.....If you have alternating nodes, usually that's a good sign they are good to go. Also, remember that they will double to triple in size. Looking at those they will probably only double since they look like a heavy indica.

Yea, one is definitely indica (it is much bushier with fatter leaves than the other three). They do not have alternating nodes yet though. Do you still feel that I can put them into flower?

Would it be better to repot into 3 gallon containers and wait for a week before flowering? Maybe they will alternate nodes by then.

If not a big deal then I guess I can repot today and let them begin step 2.

Your branches that are growing out the shoots are alternating from what I can see in the pictures. I could be wrong. They look fine to me though. Transplant them into their permanent home. Give it about a week/week1/2 and then flip the light.
Then, if you don't have way of checking trichomes in the following month (or 2). Go to radioshack and purchase a pocket microscope for $12.

Ah, thank you very much. I thought the alternating nodes were the branches coming off of the main stem but I guess they can be off the main branches as well. Still very new to this. Thank you for clearing that up for me.

Into their new homes they go. I already have that exact microscope from radio shack. :) I have seen many posts about that microscope so I figured I should get one.

Thank you for your help. Good growing.